diff --git a/docs/index.md b/docs/index.md
index 8112550..0062bde 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -20,6 +20,10 @@ description: |-
 
 ### Optional
 
-- `api_version` (Number) Choose which version of the api you would like to use 1 or 2. Default is `2`
+- `api_version` (Number) Choose which version of the api you would like to use 1 or 2 (default is 2)
 - `bearer_token` (String) The bearer token to be used to access harbor. Will take precedence over username and password if set
 - `insecure` (Boolean) Choose to ignore certificate errors
+
+### Environment variables
+
+The provider can also be configured via environment variables: `HARBOR_URL`, `HARBOR_USERNAME`, `HARBOR_PASSWORD`.
diff --git a/templates/index.md.tmpl b/templates/index.md.tmpl
index f792e6a..86639f6 100644
--- a/templates/index.md.tmpl
+++ b/templates/index.md.tmpl
@@ -24,6 +24,10 @@ For example, the {{ .SchemaMarkdown }} template can be used to replace manual sc
 
 ### Optional
 
-- `api_version` (Number) Choose which version of the api you would like to use 1 or 2. Default is `2`
+- `api_version` (Number) Choose which version of the api you would like to use 1 or 2 (default is 2)
 - `bearer_token` (String) The bearer token to be used to access harbor. Will take precedence over username and password if set
 - `insecure` (Boolean) Choose to ignore certificate errors
+
+### Environment variables
+
+The provider can also be configured via environment variables: `HARBOR_URL`, `HARBOR_USERNAME`, `HARBOR_PASSWORD`.